1. Field of the Invention
The present invention relates in general to packaging devices and methods. In particular, the present invention relates to an improved apparatus and method for securely sealing packages, and in particular food containers.
2. Description of the Related Art
In recent years it has become common to package food items for human consumption within inexpensive plastic containers. Such containers typically take the form of a "clamshell" container, a shallow tray and covering lid commonly employed for salads, a substantially flat cake plate with covering dome, or a jug having a wide opening and a snap-on lid. In general, the containers include a top and bottom tray (the term "tray" as used hereafter being used to describe and encompass each of those elements in the preceding sentence), one or both of which have sidewalls. The free edge or edges of the sidewalls are fixed in proximity such that the top and bottom trays together define a closed cavity. Various interengaging tongues and lips will maintain the top and bottom trays in the closed configuration. In the case of the "clamshell" type container the top and bottom trays are connected with an integral living hinge which also may be characterized as a portion of the means for retaining the trays together in the closed position.
While such containers are convenient to provide consumers with inexpensive ready to eat foods, such as salads or sandwiches, the inter engaging elements to maintain the trays in the closed position are often difficult to be placed in their fully fixed position. For example, in the "clamshell" containers a single corner portion of the inter engaging means may be placed in its proper configuration, thus holding the trays in a near-closed position, yet not be engaged in other areas. In such a situation the container often appears to be fully closed, yet will allow fluids and small solid particulates to escape from the container should it be tipped.
An even greater problem with such containers is the ease of tampering with the contents. Since the containers may be opened and reclosed without damage, it is possible that the food contained in the container has been altered or partially removed.
Additionally, it is often the case that, while the food items are ready to eat, the food stored in the container may be more appealing to the customer after further preparation. A typical example would be exposure of the food item to microwave radiation for heating. In such situations it is often desirable to provide the customer with an indication that the product may be more enjoyable upon further preparation, or to provide instructions for such preparations. To provide a reminder to the customer of such information, it has been known to affix a small label to the exterior of the container. Such label will include the information to be conveyed, such as the phrase "delicious when heated". Other information, such as promotional information or indicia for the seller may , of course, also be desired to be provided.